Quote Originally Posted by Evertjan Dondergoor View Post
In a program with a 'window' the window_handle will always have a value, but in a program without a window (like webapp or a background process without UI) the window_handle will be 0. I do not think there is a reason to check if it is > 0. It can be valid as you have found out already.
I'm mostly puzzled by it ceasing to work across 19.1 and 20.0 simultaneously except in a small number of cases. It has to be the point where it's triggered, I suspect, though I spent an unhappy hour or two trying to work out if there was a stray version somewhere.

In each case there is a current UI, albeit the program has finished doing actual work, and the thing being dostartdocument-ed is a summary or error report.